Ok,I am stuck on my tank install and I really could use some help, as I may have made the wrong choice in choosing this tank. Please bear with me as I explain my problem.After doing the research and taking all the measurements I thought I needed to take, I opted for this tank, a mustang tank ( 65 to 68 ) from tanks inc. This tank has been installed in other chevy frames with some modifications.http://www.tanksinc.com/cartimages/prod_zm_311.jpg The measurements for this tank are 32-3/4''x24-1/2''x7-1/2'' deep..

This is what was in there before, the blazer tank.. pic#1

As I position the tank to try to fit between the frame rails, I see that it won't squeeze in at all. the measurements for the in side of the frame is 33-1/2'', the bottom side of the mustang tank is 29'' even from end to end.Pic#2 new tank up against the frame

In pic # 3, this is where I got stuck..The bottom part of the frame that you see is 3'' wide. In order for me to slide the tank between the frame I would have to cut approx. 1-1/2'' from each side. That seems to be a bit too much I think with out loosing any strength integrity of the frame. Correct?

In pic #4 The top part of the frame towards the front is 3'' wide and tappers down to 2-1/2'' towards the rear, but the bottom portion of the frame is 3'' even front to rear.

I don't know if its safe to cut off from the bottom portion-of the frame as I mentioned before with out making it weak..

I don't know what exactly I need to do here and could use some help or advice. I was told from the guy's at Tanks that people use this tank for a lot of under bed conversions with minimal issues. Is there something I can do to get this tank to work here? I'm not even sure if I can return it. This is a real headache right now.

Thanks everyone for any help you can offer. Sorry for the lengthy post, but thought it was necessary.......

I'm getting ready to order a Mustang tank and want it to go smoothly...

Interested to see how this went as well??....if do a image search....there's guy who put one in a 66(think??)...over jalopy journal years ago.....be good tank for doing rear mount if fits for sure!Posted via Mobile Device

The $218 one is for EFI and it does have internal modifications and external changes. Its nothing like the $80 tank and it won't work for a stock mustang car. Its coated steel and has the proper holes for EFI pump and sender. The $80 stock tank has one hole near the bottom of the tank for a pickup and sender. It won't work for EFI at all without a lot of modifications.

that's not at all true. I have been using a stock 65 Mustang tank without any fuel tray for EFI at all for over two years and that's with a 5.3 fuel injected motor. Unless you are slomning or quarter mileing on a near empty tank, you will not go side to side enough for the fuel to go away from the pickup

If you want to see how it's done check out my 49 build in my signature.

"The $218 one is for EFI and it does have internal modifications and external changes. this is definitely true

Its nothing like the $80 tank and it won't work for a stock mustang car. This is also trueif your attempting to use a stock sender pickup on the EFI tank .

it Its coated steel and has the proper holes for EFI pump and sender. Again also true.

The $80 stock tank has one hole near the bottom of the tank for a pickup and sender. also true.

It won't work for EFI at all without a lot of modifications"It would work with a stock sender to plug the hole in the bottom and using an pump like a PA series. or an external pump with the stock sender and pickup so its half true

I can agree with you here somewhat, You may or may not have a starvation issue without the tray but for the price of it I prefer to have a tray in it or a pump that has a cup.

"The $218 one is for EFI and it does have internal modifications and external changes. this is definitely true

Its nothing like the $80 tank and it won't work for a stock mustang car. This is also trueif your attempting to use a stock sender pickup on the EFI tank .

it Its coated steel and has the proper holes for EFI pump and sender. Again also true.

The $80 stock tank has one hole near the bottom of the tank for a pickup and sender. also true.

It won't work for EFI at all without a lot of modifications"It would work with a stock sender to plug the hole in the bottom and using an pump like a PA series. or an external pump with the stock sender and pickup so its half true

I can agree with you here somewhat, You may or may not have a starvation issue without the tray but for the price of it I prefer to have a tray in it or a pump that has a cup.

Okay, for the price it is good to have a tray. What I run is $70 mustang tank. I'm using the stock fuel pickup, an external pump, and a corvette style fuel filter with a return. On top of the tank I just drilled with a hole–saw for the stock brand-new sender. And I put a brass 90° elbow for the return into the tank. I was just saying that it wasn't necessary to have a tray.

Okay, for the price it is good to have a tray. What I run is $70 mustang tank. I'm using the stock fuel pickup, an external pump, and a corvette style fuel filter with a return. On top of the tank I just drilled with a hole–saw for the stock brand-new sender. And I put a brass 90° elbow for the return into the tank. I was just saying that it wasn't necessary to have a tray.

I saw your page on the setup. Most likely with that short of a return it may not starve. I would expect it to blow any air back into the tank rather quickly.

Regular cheap tank. Sweat out the stock fill pipe and added the tanks inc filler myself, then put the vent/ roll over valve in the cap. I've got some 3/8" weld in bungs to add in the bottom corner of the tank. Probably won't bother with a sump. Mechanical pump on the motor, and possibly an external fuel pump on the frame rail of we need it. It'll be a turbo & efi motor. Had to trim the insides of the frame rail 3/4" on each side for it to slide in, and then I nutserted the tank and bolted it under the top framerail so it looks like it's supposed to be there. Still need to add a rear cross member back in. Probably just 2x3 angle so it captures the tank, but it can be dropped and slide back out if needed.

Is your truck a '57 stepside?
You using a stock rear bumper, or roll pan?
Did you end up using a flexible hose from the fuel neck, & a flip up or down license plate door.
I assume that bend for the fuel neck is a 70 degree from tanks inc.
I paid a fab guy to 4 link my rear, & install the mustang tank, but he shimmed the tank down below the frame rails, then he installed a 90 degree rubber fuel neck.
Looks like crap, & can't put a fuel nozzel in it.
I'm thinking i need remove the 2" sq tubing shims, install the same fuel neck as you.
Please advise

He mounted above the lower rail and had to trim the frame to accommodate the tank. I remember selling him a 70 degree neck and it should drop just under the rear cross sill. Use a 2" ID short rubber hose to connect to a fill neck and you should be good to go. You can get a flip down plate hanger to hide it and you will have to fab a little hanger for the fill neck.

He mounted above the lower rail and had to trim the frame to accommodate the tank. I remember selling him a 70 degree neck and it should drop just under the rear cross sill. Use a 2" ID short rubber hose to connect to a fill neck and you should be good to go. You can get a flip down plate hanger to hide it and you will have to fab a little hanger for the fill neck.

My brother came over today, pulled the bed off.
So from what I've read here, & what your saying, is in order to slide it in between the frame rails, the rear cross member needs to be relocated further back, & 1 &1/2" inches has to be trimmed from the frame rails.
Another option I'm considering is the 59-60 car gas tank, & cut down the fuel neck.
Would either install result in about the same ground clearance?

I Removed the mustang gas tank that my fab guy installed.
He mounted it below the frame rails, & double shimmed it with square tube channel & dropped it down even further.
Looks like crap, hanging down way to low, & the full 90 fuel hose he used won't allow me to put a fuel nozzle in.
I'm thinking about grinding off the spacers he welded in, & bolting directly on the bottom of the frame rails, instead of inside the frame rails.
Can't see gaining that much more clearance if installing inside the rails.
And I won't have to relocate the cross member, or trim the frame rails.
Seems this would still allow me to use a 90 degree fuel neck, & have the cap behind a flip down license plate.
If you want something done right, gotta do it yourself.

I agree on removing the tube frame and not putting inside the rails. I would not use a 90 on the fill. Its to short and it will back flow when you fill it. get a new tank neck like the one I posted (70 degree) so the hose slopes down toward the tank.

I decided to scrap the mustang tank option, & decided to go with the 59-60 car gas tank option.
So if anybody in Houston area needs a NEW mustang tank, I'll be selling mine.
As far as installing a flip up/down license plate to access the filler neck, I assume this is bolted to the bottom cross sill?
Or do I need to fabricate something for that?
Looks to me it can only be a flip up if bolted to the cross sill, a flip down seems like it would be too high, & hit the bottom of the tail gate.

Is your truck a '57 stepside?
You using a stock rear bumper, or roll pan?
Did you end up using a flexible hose from the fuel neck, & a flip up or down license plate door.
I assume that bend for the fuel neck is a 70 degree from tanks inc.
I paid a fab guy to 4 link my rear, & install the mustang tank, but he shimmed the tank down below the frame rails, then he installed a 90 degree rubber fuel neck.
Looks like crap, & can't put a fuel nozzel in it.
I'm thinking i need remove the 2" sq tubing shims, install the same fuel neck as you.
Please advise

sorry i never saw this, so its a late reply...
yes its a stepside
stock rear bumper
yes that fuel neck with the bend came with the tank from tanks inc
yes i used a flexible fuel hose. i made my own flip down license plate by combining the stock license plate braket and a universal flip down bracket. getting the custom braket welded to the rear sill was not an easy job. an old friend of mine with 40 years of welding / metal work experience was able to do it.

sorry i never saw this, so its a late reply...
yes its a stepside
stock rear bumper
yes that fuel neck with the bend came with the tank from tanks inc
yes i used a flexible fuel hose. i made my own flip down license plate by combining the stock license plate braket and a universal flip down bracket. getting the custom braket welded to the rear sill was not an easy job. an old friend of mine with 40 years of welding / metal work experience was able to do it.

Thanks its my first time doing a rat rod resto on a vwhical. Gonna do it up through the wood bed onice I get the wood in lol still trying to figure out with what I want to do with the truck this is what it looked like before I tore it down to the frame want it lower but I really don't have a shop to work on it so I have been doing all my work outside on the gravel. It will get there in time just enjoy these trucks I guess thats why I have 3 of them lol